From: Eric Jacoboni <jaco@...>
Date: 2006-02-09T08:08:30+09:00
Subject: About GetoptLong and exceptions

Hi,

I try to play with GetoptLong but i don't know how to handle
exceptions for this class (i've no found any documentation on
this). Here my toy snippet :


=-=-=-=-=-=-=-=-=-=-=-=-
require 'getoptlong'

def print_usage
  STDERR.puts <<-FIN
  Usage: 

    #{$0} [--bla | -b ] [--nbre=val | -n val | -c val] 
          [--longueur[=val]�| -l [val] ] fichier1 [fichier2]
  FIN
  exit(1)
end

options = GetoptLong.new(
                 ["--bla", "-b",  GetoptLong::NO_ARGUMENT],
                 ["--nbre", "-n", "-c", GetoptLong::REQUIRED_ARGUMENT],
                 ["--longueur", "-l", GetoptLong::OPTIONAL_ARGUMENT])

 
begin
   options.each do |opt, arg|
      case opt 
         when "-b"
           bla = true
         when "-n"
           cpteur = arg
         when "-l"
           longueur = (arg ? arg : 10)
       end  # case
   end # each
rescue Exception
   print_usage
end

# Now, parsing ARGV
(...)
=-=-=-=-=-=-=-=-=-=-=-=-

So, i expect a command line as "ruby toy.rb -z" would only print the
"Usage" message. But here's what i get:

toy.rb: invalid option -- z
Usage: 

toy.rb [--bla | -b ] [--nbre=val | -n val | -c val] 
      [--longueur[=val]?| -l [val] ] fichier1 [fichier2]


Where the "toy.rb: invalid option -- z" comes from? Unless i have not
fully understood the Ruby exception mechanism, it seems that my rescue
clause would handle all exceptions, isn't it ?

Any clue?
-- 
Eric Jacoboni, ne il y a 1442879654 secondes